Apparatus for cleaning filter plates and the like

ABSTRACT

A stack of flat plates consisting of rectangular frames spanned by filter cloth, normally held together under pressure, is overlain by a rail extending lengthwise of the stack and carrying a transverse beam on which a carriage supports a cleaning unit introduceable from the side into the space between two separated filter plates. The unit comprises a pair of horizontal or vertical spray tubes, each extending over the full width or height of the filter cloth, which are vertically or horizontally movable with the aid of a pair of guide rollers riding on opposide edge portions of the frame when driven apart by a fluidoperated expander. The correct positioning of the beam with reference to the separated filter plates can be ascertained by a centering device adapted to be lowered into the intervening space, this device including two spreadable arms terminating in respective sensing rollers.

United States Patent Stadie et al.

APPARATUS FOR CLEANING FILTER PLATES AND THE LIKE Inventors: Werner Stadie, Kettwig; Kurt Sperling, Essen; Rolf Deubner, Bochum; Werner Pattberg, Essen, all of Germany Pumpen und Maschinenbau Abel Kommanditgesellschaft, Essen, Germany Filed: Apr. 5, 1972 Appl. No.: 241,199

Assignee:

Foreign Application Priority Data Apr. 21, 1971 Germany P 21 19 295.0 Apr. 21, 1971 Germany P 21 19 296.1

US. Cl. 134/43, 134/57 R, 134/172 Int. Cl B08b 3/02 Field of Search 134/43, 46, 57 R,

References Cited UNITED STATES PATENTS 11/1971 Busse et a1 134/172X 3,633,651 1/1972 Ruhlandt 134/172 X FOREIGN PATENTS OR APPLICATIONS 6,516,120 12/1965 Netherlands 134/172 Primary Examiner-Robert L. Bleutge Attorney-Karl F. Ross [57] ABSTRACT A stack of fiat plates consisting of rectangular frames spanned by filter cloth, normally held together under pressure, is overlain by a rail extending lengthwise of the stack and carrying a transverse beam on which a carriage supports a cleaning unit 'introduceable from the side into the space between two separated filter plates. The unit comprises a pair of horizontal or vertical spray tubes, each extending over the full width or height of the filter cloth, which are vertically or horizontally movable with the aid of a pair of guide rollers riding on opposide edge portions of the frame when driven apart by a fluid-operated expander. The correct positioning of the beam with reference to the separated filter plates can be ascertained by a centering device adapted to be lowered into the intervening space, this device including two spreadable arms terminating in respective sensing rollers.

13 Claims, 6 Drawing Figures Hill PATENIEDUECZSIHH $780,747 suizra'nr 5 FIG.2

PATENTEDUECZSW 3.780.747

SHEET 3 U? 5 FIG.6

APPARATUS FOR CLEANING FILTER PLATES AND THE LIKE Our present invention relates to an apparatus for cleaning a set of stacked plates, more specifically (though not exclusively) filter plates of the type wherein a generally rectangular frame is provided with filter cloth spanning one or both sides thereof.

A stack of such filter plates may be inserted in a duct or chamber traversed by a fluid to be purified and, when so used, may be longitudinally compressed by hydraulic or pneumatic means to hold the plates in closely packed. For cleaning the filters, the longitudinal pressure is released whereupon the plates may be separated to facilitate the removal of adhering dust particles by a cleaning fluid such as water dispensed under high pressure from nozzles introduced into the space between adjacent plates.

For a simultaneous cleaning of confronting surfaces of two momentarily separated filter plates or the like, it is desirable to use two nozzle carriers, such as a pair of parallel perforated tubes extending parallel to a major plate dimension and moveable at right angles thereto, which are introduced simultaneously into the intervening space and should come to lie as close as possible to their respective surfaces for the sake of efficiency. If the spacing of the plates is subject to variation, or if the assembly is not accurately centered between two plates, one of these surfaces may not be cleaned sufficiently in a normal operating cycle so that the same may have to be repeated.

It is, therefore, the object of our present invention to provide an apparatus of the type set forth in which the desired relative positioning of the plates to be cleaned and the associated nozzle carriers is automatically brought about and maintained throughout the cleaning cycle so that the efficiency of the action is independent of the judgment of an operator.

This object is realized, pursuant to our invention, by the provision of mounting means for a support serving to introduce a pair of nozzle carriers into the space between two separated plates to a stack and for moving these carriers within that space to enable them to sweep the entire area to be cleaned, these nozzle carriers being provided with contact means such as end rollers engageable with marginal portions of the respective plates to guide them along their sweep. A spreader mounted on the support alternately draws the nozzle carriers to each other, thereby facilitating their insertion into the space between two plates, and drives them apart to establish firm contact between the marginal plate portions or frames and the guide rollers or equivalent contact means. This separator may be operated by fluid pressure and for this purpose may be connected to a branch of the line feeding the nozzle carriers from a source of high-pressure cleaning fluid.

Advantageously, the mounting means is in the form of a horizontal beam transverse to the stack axis, this beam being shiftable along a rail extending above the horizontally disposed stack in the longitudinal direction thereof; the support for the nozzle carriers then includes a carriage which moves along the beam and from which the nozzle carriers are suspended by a column which may be either rigid or extensible. The use of an extensible column composed of two or more telescoped members, such as a pneumatic or hydraulic jack, enables the vertical displacement of the nozzle carriers in their inserted position if these carriers are horizontal tubes or the like. Such vertical motion also serve to lift the nozzle carriers over a horizontal rod passing through apertured bottom lugs of the plates which guide them into and out of contact with one another. With vertical tubes such a rod may be cleared by a tilting motion so that an extension of the column will not be needed, except possibly for alignment purposes.

The beam serving as a track for the carriage and its column may be cantilevered on a trolley riding the rail above'the stack. We prefer, however, to support the beam at both ends by respective trolleys whose rails overlie a pair of parallel stacks bridged by the beam; the same nozzle carriers may then be used alternately for the two stacks being rotatable for that purpose about the column axis into either of two diametrically opposite positions.

According to another advantageous feature of our invention, a centering device carried on the beamsupporting trolley determines the correct alignment of the beam with the space between two separated plates, this device having a pair of arms which are swingable in a longitudinal plane of the stack and terminate in preferably roller-shaped sensors designed to contact the frames of respective plates. Switches controlled by these sensors arrest the trolley drive whenever both sensors have made contact.

The above and other features of our invention will be described in detail hereafter with reference to the accompanying drawing in which:

FIG. 1 is a somewhat diagrammatic elevational view of an apparatus according to the invention as seen in the axial direction of a stack of filter plates to be cleaned;

FIG. 2 is a top view taken on the line II II of FIG. 1, drawn to a larger scale and showing a pair of nozzle carriers in operative position;

FIG. 3 is a fragmentary cross-sectional view taken on the line III III of FIG. 1, illustrating a centering device included in the apparatus;

FIG. 4 is a view similar to FIG. 1, showing a modification;

FIG. 5 is a view similar to FIG. 2, taken on the line IV IV of FIG. 4; and

FIG. 6 is a circuit diagram serving to explain the operation of the centering device shown in FIG. 3.

Reference will first be made to FIGS. 1 and 2 for a description of an embodiment operating with horizontal nozzle carriers. A horizontal stack of filter plates, each comprising a rectangular frame 1 (here approximately square) spanned by two sets of filter cloth 2, is threaded onto a pair of parallel rods 3 traversing lugs la integral with each frame 1. These frames are also provided with upstanding brackets 1b carrying rollers 10 by which they are suspended from a pair of rails 4 formed by the lower flanges of two parallel l-beams.

The several filter plates can be axially compressed by 1 a pair of preferably fluid-actuated clamp jaws one of which has been illustrated at 5. Upon separation of these clamp jaws, the plates may be individually shifted (e.g., manually) along rods 3 and rails 4 so as to be separated for cleaning purposes. The upper flanges of beams 4 are frictionally engaged by drive rollers 10a of a trolley 10 equipped with a reversible electric motor 10b for these rollers. Trolley 10 is integral with a transverse beam 6 forming a guidetrack for a carriage 7 whose wheels 7a are powered by a reversible electric motor 7b. The opposite end of beam 6 is secured to a similar trolley riding on a pair of rails which parallel the rails 4 and overlie another stack of filter plates; carriage 7 may be driven along beam 6 toward either of these stacks. Motors 7b and 10b are independently energizable under the control of manually operated switches, one of these (associated with motor 10b) being shown at 10c in FIG. 6.

Carriage 7 supports a vertical column in the form of a preferably hydraulic jack 8 having a plunger 11. The lower end of this plunger is rigid with a horizontal bar 14 having a longitudinal slot 15 within which a pair of pivot pins 16 are slidable, this bar forming part of a spreader or expander generally designated 13. Pivot pins 16 form the junctions of two pairs of arms 17 and are biased toward each other by tension springs 19, the arms 17 being articulated to opposite ends of a pair of horizontal tubes 9 provided with spray nozzles 12. A thruster in the form of another hydraulic jack 18 interlinks the pins 16 and, when pressurized, drives them apart against the force of springs 19 so as to move the two spray tubes 9 toward respective filter plates 1, 2 between which the spreader 13 is inserted along with the tubes. A flexible conduit 21, supplied with water under pressure from a nonillustrated pump, has a branch 20 leading to the jack 18 which is also provided with a return conduit 20a. A valve 20b is operable to admit water from line 21 to tubes 9 and is parallel therewith to jack 18 while closing the drain 20a.

The ends of tubes 9 carry respective guide rollers 2 which,.upon their introduction between the two plates and actuation of spreader 13, come to bear on the vertical legs of the frames 1 of these plates along which they ride up or down as the plunger of jack 8 is retracted or extended by manual control means not shown. The pressure exerted upon the separated plates by the spreader 13 is absorbed by adjoining plates of the stack and ultimately by the clamp jaws 5 whose spacing determines the maximum distance between the plates to be cleaned.

As indicated by a dot-dash line A in FIG. 1, a cleaning cycle may'start with the tubes 9 in their bottom position and with the carriage 7 midway between the illustrated stack 1, 2 and the symmetrically positioned stack not shown.

While moving toward the stack, tubes 9 are slightly raised to clear the proximal rod 3 whereupon they are again lowered preparatorily to expansion of spreader 13. Thereafter, with the fluid line 21 opened to admit spray water to the nozzles 12, the tubes are raised as indicated by arrow B to sweep the entire surface of the confronting filter screens 2. The tube motion may then be reversed with contraction of spreader l3 and stoppage of the water flow in the bottom position between the plates and subsequent return of the spray unit to the remote position shown in FIG. 1.

Jack 8, journaled in a sleeve 70 rigid with carriage 7, has a handle 8a by which it may be rotated through l80 into an alternate position in which the tubes 9 extend in a diametrically opposite direction, as illustrated in phantom lines in FIG. 1, to serve the other stack. The jack may be indexed in its selected operating position by detents not shown in FIG. 1.

The trolley 10 also carries a centering device 23 illustrated in greater detail in FIG. 3. As shown in the latter Figure, this device comprises a pneumatic or hydraulic jack 24 with a telescoped plunger consisting.oftwo sections 24a and 24b. Two arms 25 and 25 articulated to outer section 24a, carry respective sensors 26 and 26 and are linked with inner section 24b by a pair of additional arms 27, 27' which move these sensors apart when the inner section 24b advances relatively to the outer section 24a. These two sections are in frictional engagement so that both move down together under the pressure of a fluid introduced into the cylinder of jack 24; when section 24a reaches the limit of its downward stroke, section 24b continues so that sensors 26 and 26' are swung to the left and to the right, respectively, as viewed in FIG. 3.

Each of these sensors, as shown in FIG. 6, comprises a respective roller 26a, 26a which is normally biased outwardly by a nonillustrated spring and acts upon respective switch contacts 26b, 26b included in the energizing circuit of motor 10b. The manual control switch for this motor is shown in a neutral position which it occupies after the trolley 10 has been approximately aligned with the gap between two separted filter plates. Upon the subsequent pressurization of jack 24, device 23 enters the clearance between the plates whereupon its sensors 26 and 26' move apart as described above. If, say, sensor 26 is the first to contact the frame 1 of a plate with its roller 26a, motor 10b is energized to operate in a predetermined direction designed to drive the trolley 10 to the right of FIG. 3. As soon as roller 26a of sensor 26' also makes contact, the motor circuit is opened; if contact had first been made by roller 26a, the motor would have turned in the opposite sense to move the trolley 10 to the left. In either case, therefore, that trolley with beam 6 and tubes 9 comes to rest midway between the two plates.

The system of FIGS. 4 and 5 is generally similar to that of FIGS. 1 and 2, corresponding elements having been designated by the same referenced numerals supplemented by a l in the position of the hundreds digit. The principal difference is that the tubes 109 are vertical rather than horizontal, their end rollers 122 being therefore engageable with the upper and lower edges of frames 101 to guide these tubes in a reciprocating horizontal sweep. The spreading device of FIG. 3 and the means for rotating the jack 108 about its vertical axis have been omitted in FIGS. 4 and 5 for the sake of simplicity; however, an indexing lever 108b loaded by a spring 1086 has been shown in FIG. 4 as a means for releasably locking the tubes 109 and their support in either of two diametrically opposite positions. Lever 10812 is carried on a vertical bar 108 which replaces the jack 8, 11 of the preceding embodiment and, like the former, is journaled in a sleeve 107a rigid with carriage 107. A mounting plate 129 is hinged to bar 108 at 129a as to be swingable in a clockwise sense (arrow C) for the purpose of lifting the tubes 109 across the proximal guide rod 103 (arrow D) during introduction of the tubes into the stack. This swing is brought about by the energization of a solenoid 130 working against the force of a tension spring 131 which tends to maintain the plate 129 in its illustrated vertical position. The tubes are carried on the mounting plates 29 by horizontally swingable arms 133 and articulated to the plunger ofjack 118 by links 132, 132a as indicated in phantom lines in FIG. 5. The application of hydraulic pressure to jack 118 moves the tubes 109 apart until their rollers 122 contact the confronting filter plates; springs 119 again serve to restore these tubes to their normal, closely spaced position.

It will be understood that the various operations described above could also be performed automatically,

with the aid of a programmer controlled by limit siwmountingmeans alignable with the space between I any pair of separated plates; I

support means movable on said mounting means in a direction parallel to said plates;

a pair of nozzle carriers on said support means extending alongside each other for introduction into the intervening space, said support means being operable to displace said nozzle carriers within said space to sweep substantially the entire surface of said plates;

a source of cleaning fluid under pressure connected to said nozzle carriers;

contact means on said nozzle carriers engageable with respective marginal portions of the separated plates for guidance therealong; and

spreading means on said support means connected with said nozzle carriers for driving same apart within said space to bring said contact means thereof to bear upon said marginal portions.

2. An apparatus as definined in claim 1 wherein said nozzle carriers are perforated tubes.

3. An apparatus as defined in claim 2 wherein the plates to be cleaned are generally rectangular, said tubes extending parallel to a major dimension of said plates and being displaceable with said support means in a direction parallel'to the other major dimension of said plates.

4. An apparatus as defined in claim 3 wherein the platesto be cleaned have frames spanned by filter cloth, said contact means comprising a pair of guide rollers on opposite ends of each tube engageable with opposite edge portions of said frame.

5. An apparatus as defined inclaim 3,wherein said plates are horizontally stacked and are provided with a rail extending longitudinally above the stack, said plates being suspendedfrom said rail, said mounting means being movable along said rail and including a beam perpendicular thereto, said support means comprising a carriage guided along said beam.

. 6; An apparatusas defined in claim 5 wherein said supportmeans further comprisesa column suspended from, said carriage andlinkedwith said nozzlev carriers.

7 An apparatus as defined in claim 6 wherein said 'beam bridges a pair of rails overlying respectivestacks of plates, said nozzle carriers being'swingable about said column for selective introduction between the plates of either of said stacks.

8. An apparatus as defined in claim 6 wherein said spreading'means comprises a linkage articulated to said tubes, spring means anchored'to said linkage for drawing said carriers toward each other, and fluid-actuated thrust means for displacing said linkage against the force of said spring means.

9. An apparatus as defined in claim 8 wherein said thrust means is provided with a branch connection to said source of cleaning fluid for actuation thereby.

10. An apparatus as defined in claim 6 wherein said tubes are substantially vertical but are hinged to said column for swinging about a horizontal axis to clear a lateral bottom support for said filter plates.

11. An apparatus as defined in claim 6 wherein said tubes are substantially horizontal, said column comprising an extensible pairof telescoped members.

12. An apparatus as defined in claim 1 wherein said mounting means includes a centering device suspended from'said beam for'ascertaining the relative position of said beam and said separated plates.

13. An apparatus as defined in claim 12 wherein said centering device comprises a pair of arms swingable in a longitudinal plane of said stack,-sensing means at the ends of said arms and driving means for urging said arms in opposite longitudinal directions. 

1. An apparatus for cleaning a set of stacked plates guided for separation in longitudinal direction of the stack to form a space between a pair of plates to be cleaned, comprising: mounting means alignable with the space between any pair of separated plates; support means movable on said mounting means in a direction parallel to said plates; a pair of nozzle carriers on said support means extending alongside each other for introduction into the intervening space, said support means being operable to displace said nozzle carriers within said space to sweep substantially the entire surface of said plates; a source of cleaning fluid under pressure connected to said nozzle carriers; contact means on said nozzle carriers engageable with respective marginal portions of the separated plates for guidance therealong; and spreading means on said support means connected with said nozzle carriers for driving same apart within said space to bring said contact means thereof to bear upon said marginal portions.
 2. An apparatus as definined in claim 1 wherein said nozzle carriers are perforated tubes.
 3. An apparatus as defined in claim 2 wherein the plates to be cleaned are generally rectangular, said tubes extending parallel to a major dimension of said plates and being displaceable with said support means in a direction parallel to the other major dimension of said plates.
 4. An apparatus as defined in claim 3 wherein the plates to be cleaned have frames spanned by filter cloth, said contact means comprising a pair of guide rollers on opposite ends of each tube engageable with opposite edge portions of said frame.
 5. An apparatus as defined in claim 3 wherein said plates are horizontally stacked and are provided with a rail extending longitudinally above the stack, said plates being suspended from said rail, said mounting means being movable along said rail and including a beam perpendicular thereto, said support means comprising a carriage guided along said beam.
 6. An apparatus as defined in claim 5 wherein said support means further comprises a column suspended from said carriage and linked with said nozzle carriers.
 7. An apparatus as defined in claim 6 wherein said beam bridges a pair of rails overlying respective stacks of plates, said nozzle carriers being swingable about said column for selective introduction between the plates of either of said stacks.
 8. An apparatus as defined in claim 6 wherein said spreading means comprises a linkage articulated to said tubes, spring means anchored to said linkage for drawing said carriers toward each other, and fluid-actuated thrust means for displacing said linkage against the force of said spring means.
 9. An apparatus as defined in claim 8 wherein said thrust means is provided with a branch connection to said source of cleaning fluid for actuation thereby.
 10. An apparatus as defined in claim 6 wherein said tubes are substantially vertical but are hinged to said column for swinging about a horizontal axis to clear a lateral bottom support for said filter plates.
 11. An apparatus as defined in claim 6 wherein said tubes are substantially horizontal, said column comprising an extensible pair of telescoped members.
 12. An apparatus as defined in claim 1 wherein said mounting means includes a centering device suspended from said beam for ascertaining the relative position of said beam and said separated plates.
 13. An apparatus as defined in claim 12 wherein said centering device comprises a pair of arms swingable in a longitudinal plane of said stack, sensing means at the ends of said arms and driving means for urging said arms in opposite longitudinal directions. 